Due to the small size of present generations of semiconductor or electronic packages and in order to achieve economies of scale, a plurality of electronic packages are formed on a single substrate during manufacture of the packages. Such plurality of packages are sometimes separated by sawing after they are molded to protect the integrated circuits comprised in the packages, such as in the case of Chip-Scale Ball-Grid Array (“CSBGA”) packages. Since sawn residue in the form of dirt and small particles of contamination is created during sawing, handling of sawn (separated) CSBGA packages includes cleaning after sawing. A top side of the sawn packages is usually cleaned by cooling water applied to the packages during the sawing process. The cooling water serves not only to cool the saw blades and packages, but also to wash away residue formed during sawing. However, a bottom side of the packages cannot be cleaned in this way as the bottom side is resting on vacuum pads of a saw jig or other attachment surface to hold the packages during sawing, and are in close contact with the attachment surfaces. This contact limits the effectiveness of cleaning in this way.
There are generally two approaches that are typically adopted when handling the sawn packages, namely a nesting approach and a non-nesting approach. The nesting approach is illustrated by U.S. Pat. No. 6,165,232 (“Method and Apparatus for Securely Holding a Substrate during Dicing”), U.S. Pat. No. 6,187,654 (“Techniques for Maintaining Alignment of Cut Dies during Substrate Dicing”) and U.S. Pat. No. 6,325,059 (“Techniques for Dicing Substrates during Integrated Circuit Fabrication”). Generally, a nesting mechanism, which includes a grid arrangement that defines openings which receive the plurality of packages, is arranged to support a substrate having a plurality of packages during a dicing process. Using this nesting mechanism, the plurality of electronic packages may be lifted after dicing. Using the nesting approach, adoption of water jets positioned above and below the raised nesting mechanism holding the sawn packages is a common method for cleaning both top and bottom sides of the packages.
A problem with this method of cleaning sawn packages is that the grid structure may block the water jets from reaching certain portions of the packages. As a result, washing may not be thorough. Furthermore, the smaller the packages, the more difficult it is to hold the packages properly during washing with pressurized water jets.
The non-nesting approach is illustrated by US patent publication number 2002/0133971, where there is no grid arrangement to hold the individual sawn packages and the sawn packages are not lifted. For the non-nesting approach, running water introduced from below the packages may be used to rinse the bottom side of the separated packages by supplying water or other cleaning fluid through fluid inlets in a platform supporting the packages. As a result, the bottom side of the packages is rinsed by this operation.
However, cleaning the bottom side of separated packages just by using running water is a rather gentle way to wet the bottom surface and dilute the dirt and contamination adhering onto the bottom surfaces of the packages. If the dirt or contamination is sticky, this method cannot thoroughly remove all the dirt or contamination.